It has been found with existing fittings that they are either too complex in construction and do not work, or that the design is too simplistic and either do not work efficiently or fail under pressure or in operation. Examples of prior art hose couplings are to be found in U.S. Pat. Nos. 4,146,288 (Ramsay), 3,831,984 (Kutina) and 2,250,199 (Kelly); Australian patent application Nos. 78949/87 (Bortolin), 85889/82 (Mining Supplies (Minsup) Pty Ltd) and 27474/67 (Lindsay); and International Patent Publication No. WO91/00469 (Hampel Engineering Pty Ltd), now Australian Patent No. 642654.
Hampel has attempted to overcome the problems or differences of the prior art by providing, a universal fluid line interlocking connector, which has inherent problems in that the main body cannot be economically mass produced due to the design of its components. In addition, at least four main body fittings are required to provide standard fluid line connections between, for example, a water tap, hose retention, hose nozzle and accessories such as sprinklers, and the like.
In addition, Hampel's hose retention design is deficient because the hose disengages when the mains water pressure is high, and it tends to leak.